The present invention relates to the art of ornamental accessories for fingernails, and, in particular, to an artificial fingernail having a pre-applied adhesive layer fixed thereto.
It has been known in the art of adorning the hands to provide ornamental fingernail accessories made from thin, molded plastic members manufactured generally in the shape of a fingernail. Typically, the wearer must apply an amount of a liquid bonding adhesive to the accessory and/or the natural nail and affix the accessory to the nail. Usually the wearer must wipe or trim away any excess adhesive and then wait several moments until the adhesive dries to ensure that the accessory is secured to the nail. When it is desired to remove the accessory, the wearer typically must soak the fingernail with the attached accessory in a solvent for a sufficient amount of time to dissolve the adhesive. Such process is difficult, time consuming and damaging to the natural fingernail.
An alternative to this process is set forth in U.S. Pat. No. 4,745,934 to Mast et al. which discloses an adhesive press-on tab system for attaching artificial fingernails to the wearer""s natural nails. The tabs are essentially double-sided adhesive tape with removable liners that are interposed between the artificial fingernail and the natural fingernail. However, applying the tabs and fingernail accessories is still time consuming and cumbersome. Additionally, the stacking of the tab and accessory results in a nail that does not look natural and is prone to being dislodged.
Attempts have been made to provide an ornamental fingernail accessory having a pre-applied pressure sensitive adhesive layer with varying degrees of success. For example, U.S. Pat. No. 5,415,903 to Hoffman et al. discloses a self adhesive laminate having an adhesive composition made of an acrylate copolymer requiring acrylic acid and titanium chelate ester. U.S. Pat. No. 6,042,679 to Holt et al. discloses that an acrylic pressure sensitive adhesive known in the art can be used in a method for treating damaged fingernails. U.S. Pat. No. 5,044,384 to Hokama et al. discloses that a pressure-sensitive adhesive known in the art can be used in a method for accomplishing a rapid and durable manicure. U.S. Pat. No. 4,860,774 to Becker discloses that a commercially available pressure-sensitive adhesive can be used in a method for fingernail reinforcement. In addition, several other patents generally disclose pre-applying an adhesive to an artificial fingernail.
Some of the problems associated with the artificial fingernails of the prior art include weak adhesive strength, damage to the natural nail, short adhesive shelf-life, non-reusable adhesives, a cosmetically unappealing appearance and time-consuming or difficult application. Accordingly, it would be desirable to provide an ornamental fingernail accessory that solves these shortcomings of the prior art in a commercially efficient manner.
The present invention is an ornamental accessory for a fingernail comprising an overlay having a reusable pressure-sensitive adhesive layer pre-applied to a bottom surface thereof for application and bonding to the wearer""s natural nail, and a method of making the same.
The adhesive formulation is a copolymer of acrylic ester and vinyl acetate. The pre-applied adhesive is formed from an aqueous acrylic copolymer emulsion comprising about 35% water and 65% copolymer. Preferably, the bottom surface of the overlay to which the adhesive is applied is textured to enhance adhesion of the adhesive layer. The adhesive layer exhibits superior peel strength and is easily applied to the overlay. The adhesive layer may also include glitter or may be colored for decorative purposes. The overlay is made from a mixture of ABS plastic and a polycarbonate and may take the form of a fingernail cover or a fingernail tip.
In a method for forming a pre-glued ornamental fingernail accessory, an overlay having the shape and size of a natural fingernail is formed and an aqueous copolymer emulsion, as described above, is applied to a bottom surface of the overlay. The emulsion is allowed to cure whereby a substantial portion of the water in the emulsion is evaporated to form a reusable pressure-sensitive adhesive layer fixed to the overlay. The pressure-sensitive adhesive layer is reactivated by adding an aqueous solution to the cured aqueous copolymer emulsion.
As a result of the present invention, an artificial nail having a pre-applied adhesive layer is provided which is easily attached to the natural fingernail. The significantly improved adhesive layer is reusable so that the wearer can easily remove and reattach the artificial nail as desired without damaging or leaving adhesive on the natural nail.
For better understanding of the present invention, reference is made to the following description, taken in conjunction with the accompanying drawings, and its scope will be pointed out in the appended claims.